%L publicatio24762
%T Benchmark Ab Initio Characterization of the Abstraction and Substitution Pathways of the Cl + CH3CN Reaction
%J JOURNAL OF PHYSICAL CHEMISTRY A
%O Export Date: 20 June 2022            
            CODEN: JPCAF            
            Correspondence Address: CzakĂł, G.; MTA-SZTE LendĂźlet Computational Reaction Dynamics Research Group, Rerrich BĂŠla tĂŠr 1, Hungary; email: gczako@chem.u-szeged.hu            
            Funding details: Magyar TudomĂĄnyos AkadĂŠmia, MTA            
            Funding details: Emberi EroforrĂĄsok MinisztĂŠriuma, EMMI, 20391-3/2018/FEKUSTRAT, TKP2021-NVA-19            
            Funding details: Nemzeti KutatĂĄsi FejlesztĂŠsi ĂŠs InnovĂĄciĂłs Hivatal, NKFIH, K-125317            
            Funding details: Nemzeti KutatĂĄsi, FejlesztĂŠsi ĂŠs InnovaciĂłs Alap, NKFIA, TKP2021-NVA            
            Funding text 1: We thank the National Research, Development and Innovation Office–NKFIH, K-125317; the Ministry of Human Capacities, Hungary grant 20391-3/2018/FEKUSTRAT; project no. TKP2021-NVA-19, provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme; and the Momentum (Lendület) Program of the Hungarian Academy of Sciences for financial support.
%V 126
%R MTMT:32895238 10.1021/acs.jpca.2c01376
%I szte
%P 2802-2810
%X We investigate the reaction pathways of the Cl + CH3CN system: hydrogen abstraction, methyl substitution, hydrogen substitution, and cyanide substitution, leading to HCl + CH2CN, ClCN/CNCl + CH3, ClCH2CN + H, and CH3Cl + CN, respectively. Hydrogen abstraction is exothermic and has a low barrier, whereas the other channels are endothermic with high barriers. The latter two can proceed via a Walden inversion or front-side attack mechanism, and the front-side attack barriers are always higher. The C-side methyl substitution has a lower barrier and also a lower endothermicity than the N-side reaction. The computations utilize an accurate composite ab initio approach and the explicitly correlated CCSD(T)-F12b method. The benchmark classical and vibrationally adiabatic energies of the stationary points are determined with the most accurate CCSD(T)-F12b/aug-cc-pVQZ energies adding further contributions of the post-(T) and core correlation, scalar relativistic effects, spin-orbit coupling, and zero-point energy corrections. These contributions are found to be non-negligible to reach subchemical accuracy. Š
%D 2022
%N 18
%A  TĂłth Petra
%A  SzĹącs TĂ­mea
%A  CzakĂł GĂĄbor